Why high magnetic fields

High magnetic fields are used in Material Science, Nanotechnology, Chemistry, and Life Sciences. The magnetic field can be used as an analytic method to determine electronic properties of materials, find atomic positions in molecules or to obtain images of the internal structure of living beings. It also serves to produce new states of matter, in, e.g. quantum Hall Effect devices, quantum materials, or nanostructures. Nobel prizes related to high magnetic field have been listed in Oportunities in High Magnetic Field Science to be around 19, including prizes in Medicine (2003), Physics (2003) and Chemistry (2002). In later years, A. Geim and K. Novoselov (Fig. 1) discovered some of the peculiar properties of graphene in high magnetic field measurements (Fig. 1b, see http://onnes.ph.man.ac.uk/nano/Publications/Naturemat_2007Review.pdf).

Figure 1: Buckyballs, carbon nanotubes and graphite can be built from single layers of graphene (a). The Quantum Hall Effect in graphene was observed for the first time using magnetic fields above 10T. The figure shows the presence of massless Dirac fermions and oscillations in the conductance with a period four times higher than this one observed in convencional Hall Effect. In bilayer graphene (red curve in b), the same sequence is observed except form the oscillation at zero gate voltage that is only recovered by chemical doping. In c-e, different types of Landau quantization in graphene are shown: for massless Dirac fermions (c), massive Dirac fermions in bilayer graphene (d), and the conventional sequence (e).